Comparative efficacy of mepolizumab and benralizumab in severe eosinophilic asthma: a retrospective cohort study

This real-world study compared the efficacy and the proportion of patients attaining the criteria constituting clinical remission at 12 months between mepolizumab and benralizumab in patients with severe eosinophilic asthma. This retrospective cohort study was conducted at two tertiary medical centers in Taiwan between January 1, 2018, and June 30, 2024. Patients with severe asthma who received continuous treatment with either mepolizumab or benralizumab for a minimum of 12 months were included. Pulmonary function parameters, asthma exacerbation rates, Asthma Control Test (ACT) scores, peripheral blood eosinophil counts, and asthma remission status were assessed at baseline and after 12 months of treatment. A total of 60 patients were included, with 34 receiving mepolizumab and 26 receiving benralizumab for the treatment of severe asthma. After 12 months, the benralizumab group showed a significant improvement in pulmonary function, with mean FEV₁% increasing from 61.6% to 69.5% (∆FEV₁%: +7.9; p = 0.001). Both groups exhibited significant reductions in blood eosinophil counts: −487.1/μL in the mepolizumab group (p < 0.001) and −520.3/μL in the benralizumab group (p < 0.001). The criteria constituting clinical remission at 12 months were met in 44.1% of patients in the mepolizumab group and 30.8% in the benralizumab group, with no statistically significant difference between the groups. Both treatments were similarly effective in reducing exacerbation frequency and enabling attainment of clinical remission criteria at 12 months, tapering off oral corticosteroids, and improving symptom control. After 12 months of treatment, mepolizumab and benralizumab demonstrated comparable efficacy in asthma control, exacerbation reduction, and clinical remission in patients with severe eosinophilic asthma. However, benralizumab showed a tendency toward greater improvement in lung function.